Champion Rafael Nadal pulled rank over a teenaged pretender and Roger Federer enjoyed a brisk workout when the world's top two players began their pursuit of the French Open crown on Tuesday.

World number one Federer completed a clinical 6-4, 6-2, 6-4 first-round win over American Michael Russell in a contest which spilled over to a second day after drizzle had washed away all but 14 matches on the opening two days of the claycourt event.

Juan Martin Del Potro appeared to be getting out of hand when he grabbed a 5-3 lead in the opening set against Nadal but it was not long before the Spaniard restored order and recorded a 7-5, 6-3, 6-2 win.

"It was tough mentally as he had less pressure on him and that made him very dangerous," said Nadal, who has never been beaten at Roland Garros and is aiming for a hat-trick of titles.

Andy Roddick and Nadia Petrova suffered a recurring nightmare, sliding out in the first round for the second year running.

American third seed Roddick was once again tormented by the red clay with a 3-6, 6-4, 6-3, 6-4 defeat by Igor Andreev, while 11th seed Petrova was humiliated 7-5 5-7 6-0 by 182nd ranked qualifier Kveta Peschke.

Chilean fifth seed Fernando Gonzalez will also be leaving Paris early following a 6-2, 6-2, 6-4 humbling by Radek Stepanek.

Roddick's thunderbolt deliveries had little effect on a surface slowed by the wet weather and against a player who, until nine days ago, had held the honour of being the last man to beat Nadal on clay in 2005.

Coach Jimmy Connors had guided Roddick to at least the semi-finals of every major since they hooked up last July but on Tuesday, the eight-time Grand Slam champion was powerless to change his charge's fortunes.

The man with the world's fastest serve was even out-aced 8-5 by Andreev, who ended his opponent's ordeal with a thumping smash.

'MAGIC ANSWER'

"I've been my own worst enemy here a lot of times," said Roddick, who has won just four matches in seven trips to the French capital.

"I think I can try to improve on it but I don't know if there's a magic answer."

Tripped up by Nadal in the final last year, Federer had declared before his match: "I haven't won the French Open yet but it's definitely on my wish list".

Russell, whose sole claim to fame in Paris was to hold a match point in 2001 against eventual champion Gustavo Kuerten in the last 16, was hopelessly outclassed by Federer.

"Perfect start in the three sets," declared Federer.

The Swiss maestro needs the Roland Garros trophy to become only the third man after American Don Budge and Australian Rod Laver to hold all four majors at the same time.

Nicole Vaidisova and Serbian fourth seed Jelena Jankovic lifted dampened spirits with their photogenic smiles after moving into the second round.

Playing opponents who had not won a tour match all year, Czech sixth seed Vaidisova picked apart Emmanuelle Gagliardi 6-4, 6-3 and Jankovic was merciless in a 6-2, 6-2 defeat of France's Stephanie Foretz.

Former world number one Lleyton Hewitt continued his resurgence to crush former doubles partner Max Mirnyi 6-3, 6-1, 6-3.

James Blake completed a forgettable day for the US when eight American men were beaten.